You could add that the first ascent of the main summit which is 400 m higher was done by a Polish expedition led by Andrzej Zawada by the South ridge. 4 climbers reached the summit on August the 26th (A. Zawada, A. Heinrich, I. Stryczynski et R. Szarfirski). They had one casualty when one climber fell to his death in a crevasse. At the time it was considered quite an achievement, though obviously nothing as difficult as the SW of the KC East summit. It would interesting if one of the Polish members of summipost would give you some data on that expedition.